Tube-tapering apparatus



2,1930. 1 F. MULLER 1,783,384

7 TUBE TAPERING APPARATUS Original Filed Nov. 20, 1926 4 Shets-Sheet 1 Dec. 2, 1930. F. MULLER TUBE TAPERING APPARATUS Original Filed Nov.

20 1926v 4 SHeet-Sheet 2 w w R m RN 2:

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-Dec'.2, 1930. F. MULLER TUBE TAPERING APPARATUS 4 Sheets-Sheet 3 Original Filed Nov. 20" 1925 Du -ND.

F. MULLER 1,783,384

TUBE TAPERING APPARATUS Dec; 2, 1930.

Original Filed Nov. 20 1926 L 4 SheetLs-Siwet 4 4 9 INYENTUR BY /Zwp, Awwq m Patented Dec. 2, 1930 PATENT OFFICE FRIEDECRICH MULLER, OF ELIZABETH, NEW JERSEY TUBE-TAPERING APPARATUS Application filed November 20, 1926, Serial No. 149,664. Renewed February 8, 1930.

My invention relates to a machine for varying the diameter of metal tubes and is particularly adapted for forming hollow metal shafts for golf clubs, although the machine could also be used for forming tubes for other purposes.

In order to provide requisite flexibility in the shaft of a golf club it is desirable to taper the shaft from a larger diameter at the handle to a smaller diameter close to the head of the club, and itis an object of my invention to provide a machine which will produce such a taper.

Below the waist or point of narrowest diameter of the shaft it is desirable 'to swell the shaft and then taper. the end to fit the socket in the head of the golf club, and it is another object of my invention to provide a machine which Will not only taperthe main body of the shaft, but also give the proper contour below the waist of the shaft.

Another object of my invention is to provide means for varying the angle of taper of the main body of the shaft.

Still another object of my invention is to provide means for varying the contour of a tube at various points throughout its length.

\Vith these objects in view and other objccts which will appear hereinafter, my invention consists in certain novel features of construction and combinations and arrangements of parts, which will be more fully hereinafter described and pointed out in the claims.

In the accompanying drawings,

Figure 1 is a plan view of my improved machine 5) line 66 of Fig.2;

Fig. 7 is a view in section of a fragment of the machine, the section being taken on line 7-7 of Fig. 1;

Figs. 8 and 9, respectively, are views of a draw-head and die in two positions, showing the parts in longitudinal section and Figs. 10 and 11, respectively, are views in longitudinal section of a tube before and after being formed in my machine.

My improved machine is provided with a bed 15, resembling, somewhat, the bedof a lathe. Near one end'of the bed a fixed head A at the rear of the machine, which, at one end, is connected to the feed screw by a train of gears 23 (Fig. 5), including intermediate change gears 24. The latter, as in a lathe, are adapted to be readily removed and replaced with others of a different pitch diameter to vary the ratio of speed between the. drive shaft and the feed screw. A clutch 25, at the other end of the drive shaft, serves to couple the latter to a power shaft 26 which carries a driving pulley 27 and may be belted to a source 0 power.

The live spindle 17 is hollow, and fitted within the spindle is a hollow shaft 28. The shaft 28 turns with the spindle, as will be explained below, and at the same time has a limited longitudinal movement. The hollow shaft projects out of the left-hand end of the spindle and passes through a sliding head 29 and a fixed bearing 30, the latter being carried by a bracket 31 secured to the bed of the machine. The head 29 is arranged to slide in ways 32 in the bed of the machine and carries a roller 33 which engages a groove 34 in a drum cam 35 journaled in the bed of the machine. To drive. the cam '35 I provide a transverse shaft 36 (Fig. 4) driven by the drive shaft 22 through a pair of helical gears 37. The shaft 36 which is suitably journaled in the bed of the machine, carries a worm 38 and the latter meshes with a worm gear 39 secured to the cam. As the cam is rotated through an angle of 360 degrees, the head 29 is moved along its ways b the cam groove and returned to its origina position.

To transmit the movement of the head 29 to the hollow shaft 28 the latter is provided with a bushing 40 (Fig. 3) threaded thereon and held between a pair of lock nuts 41. A set screw 42 in the bushing 41 engages a key way 43 in the shaft 28. The bushing is journaled in the head 29 and carries a thrust ball bearing 44 which bears against the left-hand face of the head 29 (as viewed in Fig. 3),

a while a collar 45 bears against the right hand being drawn to the die.

face of the head and is held in place by a nut 46 screwed upon the right-hand end of the bushing. Thus, movement of the head 29 is imparted to the shaft 28, and because movement in the left-hand direction involves a reater expenditure of energy than movement m the opposite direction, as will be explained below a ball bearing is not required at the right-hand face of the head.

Within the hollow shaft 28 is a mandrel 46 which is of smaller diameter than that of the bore of said shaft. The mandrel 46 is adapted to move longitudinally with the shaft, but is held against rotation therewith. At its outer end, i. e., the left-hand end as viewed in Fig. 3, the-mandrel 46 carries a thimble 47 screwed thereon,,and the thimble, in turn, is threaded into a bearing sleeve 48 which has an extension that enters the outer or left-hand end of the hollow shaft 28. The sleeve 48 is formed with an annular flange 49 which is engaged on opposite sides thereof by ball bearings 50 carried by the shaft 28. The sleeve 48 is clamped in a block 51 which slides in a guidewa formed in the bracket 31. Thus, by the ball bearing connection between the sleeve 48 and shaft 28, the latter is free to rotate without imparting rotational movement to the mandrel 46, but reciprocal movement of the shaft 28' is communlcated to the mandrel 46. The outer end of the mandrel 46 is squared so that it ma be readily turned by a suitable tool in the t imble 47 for adjustment longitudinally, and a jam nut 52 serves to lock the rod at the desired adjustment. Oil may be fed under pressure into the hollow shaft 28 through a tube 53 which is threaded into the block 51 and registers with a port in the sleeve 48 The pressure may be supplied by means of a pump (not shown) or other suitable means. The oil thus forced under pressure into the tube 28 will flow through that tube, and about the mandrel and the tube The oil will by the pressure be forced about the balls, fill the die and pass out at the right hand (Fig. 3) side of the die. This insures lubrication of the parts and the flowing oil washes out all scale etc. that may be present in the die or. elsewhere.

At the right-hand end of the spindle 17, as viewed in Fig. 3, the bore of the spindle is enlarged to receive a head 54 secured upon the end of the shaft 28. The head 54 carries a pair of feathers 55 which engage a pair of keyways 56 longitudinally disposed in the inner wall of the spindle. The head 54 is hollow and carries an annular die block 57, the inner wall of which tapers from a smaller diameter at the right-hand end thereof to a larger diameter at the opposite end. The dieblock is held in a seat in the head 54 by means of an annular nut 58 screwed into the end of the head. The right-hand end of the mandrel 46 projects into the die-block and is provided with a tapered end 59 which arallels the tapered face of the die-block. urrounding the rod 46 within the die-block is a ball cage 60 provided with a plurality of holes to receive hardened steel balls 61 which move radially in and out through the holes under the action of the die-block. The dimensions of the parts are such that a tube to be tapered may be introduced into the cage and upon the rod or mandrel 46 and the balls 61 will be pressed by the die-block against the tube. The purpose of this will be explained presently. The right-hand end of the cage 60 is.formed with a flange 62 which is engaged on opposite sides thereof by ball bearings 63 carried by the spindle 17. Thus while the ball cage is free to revolve it is held against longitudinal movement.

The draw head 19 carries a stud 64 which is alined with the mandrel. 46. On this stud the tube which is to be formed is fitted and held by a chuck. The chuck comprises upper and lower jaws 65 and 66 which are normally held apart by sprin s 67 (see Fig. 6). The upper jaw is mova le with respect to the lower jaw and after a tube has been fitted on the stud 64 between the jaws, a clamping screw 68 threaded into the head and provided with a handle 69 is turned until the lower end of the screw engages the jaw 66 and forces the latter tightly against the tube.

The draw head is provided with a split nut 70, Fig. 7, which engagesthe feed screw 21. The nut may be operated to close upon the screw or to open and release engagement with the screw, by meansof a handle 71 which carries a plate 72 in which are formed a pair of eccentrically curved grooves 73, Fig. 1. Pins 74 on the two jaws of the nut enter these grooves and thus by turning the handle in one direction the jaws of nut 70 will be opened while movement in the other direction will close the jaws upon the feed-screw 21.

When the nut 70 is released from the feed screw the drawhead 19 may be moved in either direction along the ways 18, by means of a worm wheel 75, shown in dotted lines in a the worm wheel ,the shaft tends to hold the dog 86 in engage- Fig. 6. The worm wheel engages the screw 21 and is carried by a shaft 76 journaled in the ii'aw head and provided with a hand wheel An automatic stop mechanism is provided to throw out'the clutch 25 at the end of each cycle of operations of the machine. In other words, at the end of each complete rotation of the cam the clutch 25 is thrown. One of the members 25' of the clutch is mounted to slide on the shaft 22. Above the shaft 22 is mounted a clutch operating rod 78 which carries a yoke member 79 adapted to engage a groove .formed in the clutch member 25'. A. compression spring 80 on the rod 78 serves to hold the clutch member 25, normally in engagement with its mating clutch member.

The right-hand end of the rod 78 is engaged B by an arm 81 of a bell crank lever, the other arm 82 of which is formed with a yoke 83 engaging an annular groove in a collar 84 on a transverse shaft 85. The shaft 85 is suitably mounted in bearings which provide for a limited longitudinal movement of the shaft. A dog 86 carried by the shaft 85 is adapted to engage a pin 87 projecting from 39. A torsion spring 88 on ment with the face of the worm wheel 39, but the shaft 85 may be turned by means of a handle 89 to clear the pin 87, whereupon the spring 80 will cause the clutch jaws to engage and vby reason of the bell crank will slide the shaft 85 forward. The parts actus ated by the shaft 22 will then start operating, and the operation will continue until the worm wheel 39 has made one complete rotation, when the pin 87 will engage the dog 86. moving the shaft 85 rearward and, through the bell crank, retracting the'clutch member 25 against the pressure of the spring 80.

The operation of my machine is as follows:

Assuming that the clutch 25 has been opened by the pin 87 and that the hollow shaft 28 whichcarriesthe die-block 57 has been moved by the cam 35 to its extremerighthand position, as shown in Fig. 3, the first op eration is to release the nut by operating the handle 71, after which the draw-head 19 is drawn to the right by means of the hand wheel 77. A metal tube 90 which is to be tapered in the machine, is now inserted in the spindle 17 through the ball cage 60 and u on the mandrel. 46. The draw-head is t en moved towa t e spindle 17 so that the stud 64 will enter the outer end of the tube 90 and the chuck jaw 66 is clamped down uponthe tube by operating the handle 69. The draw head 19 is moved close to the end of the-live spindle 17 and then the handle 71 is operated to close the nut 70 upon the screw 21. Thereafter the handle 89 is turned so as to release the dog 86 from engagement 'with the pin 87 and throw the jaws of the clutch 25 into enand the die-block 57 and 34, and it will be evident t ,gagement. Thereupon the feed screw 21 is operated to draw the draw-head 19 away from the spindle 17 thereby drawing the tube 90 slowly-out of the spindle. Inthe meantime, the spindle 17isbeing rotated by the pulley 20 and the balls 61 in the cage 60 are eing pressed against the I the tube 90 compressing the tube against the mandrel 46. While this is taking place the cam 35 is slowly drawing the shaft 28 and the mandreltoward the left and the die-block 57 being carried by the shaft 28 is slowly forcing the balls 60 inward, thus reducing the diameter of the tube 90. The travel of head 19 is much more rapid than that of the die-block 57 and the mandrel 46, and hence a very gradual taper is given to the tube 90. y referring to Fig. 9 it will be observed that as the balls 60 are moved inward by the dieblock 57 they force the tube against the pointed end portion 59 of themandrel 46, and as the taper of the portion 59 parallels the taper of the die-block 57 the balls 61 are constantly compressing the tube 90 against a correspondingly reduced portion of the mandrel the relation of the face of the dieblock and mandrel may be varied from parallel however so that any desired variation wall thickness may be obtained.

Fig. 9 shows the parts at the completion of the taper of the main body of the tube 90, mandnel 46 being here shown in their extreme left-hand posifthe draw tion. It will be understood that the taper of the tube or shaft 90 is determined by the relative speed of the feed-screw 21 and cam 35 and this may be varied as explained above by position shown in Fig. 9, the dieblock and mandrel are moved to the right at such a rate as to form the bulb 92 and then again moved to the left to form the taper 93. This irregudie-block together with the mandrel 46 is controlled b the cam roove hat any esired form may be given to, the. tube 90 by the proper form of the cam groove. In fact the use of a cam permits of veryaccurately adjusting the parts toprodue any desired form of taper and swell in the shaft 90, forit is merely necessary to introduce a standafd shaftof the desired contour in the machine,

and mount ablank camYlrum in place of the drum 35, when,

by substituting-a tracer for the roller 33, a center line for a cam groove may be drawn on the drum cam while the shaft 28 is moved by hand so that the dieblock 57 will follow the contour of the standard. Thereafter a cam groove may be cut in the cam drum along the center line drawn thereon, thus forming a cam which will accurately reproduce the standard in any number of tubes inserted in the machine. It will be understood that after the shaft 90 has been completed the die-block 57 and mandrel will be brought back to their original position, shown in Figs. 3 and 8, and the clutch 25 will be thrown out of engagement by the pin 87 engaging the dog 86.

It will be understood, of course, that the live spindle 17 is held against longitudinal movement by suitable means which, as shown in the drawings, may consist of a pair of thrust collars 94 thereon, engaging opposite faces of one of the mating members of the head stock 16. Ball bearings are provided to take the thrust of the cage 60 so as to prevent binding and jamming and soas to permit the cage to revolve freely about the tube. By reason of oil introduced into the shaft 28 through the tube 53, the balls 61 are kept constantly lubricated and danger of twisting the tube 90 during the drawing operation is obviated. As intimated above, considerable energy is required to draw the die-block 57 toward the left, because during this movement the tube 90 is being drawn to a small diameter, and for this reason the thrust ball bearing 44 is provided at the left-hand side of the head 29.

By adjusting the mandrel 46 longitudinally, the clearance between the die-block 57 and the tapered portion 59 of the mandrel may be varied, thereby varying the thickness of the wall of the tube 90.

It is obvious that by a suitable contour of cam groove 34 and proper selection of change ears 24, the contour of the tube formed by iilie machine can be widely varied, and hence, my machine is not limited to the production of shafts for golf clubs, but has a wide application for a variety of other products.

While I have described my machine in considerable detail, it will be obvious that various changes could be made in the arrangement and construction of diflerent parts without departing from the spirit and scope of my invention as defined in the following claims.

I claim,

1. Apparatus for varying the diameter of a tube, comprising, in combination, a drawhead adapted to grip the tube, a die having a variable orifice, means for moving the drawhead relatively to the die to draw the tube through the die, said means including replaceable elements for adjusting the rate of movement of the draw-head, a cam, and means controlled by the cam for varying the orificein timed relation to the draw-head.

2. Apparatus for varying the diameter of the movement of r a tube, comprising, in combination, a drawhead adapted to grip the tube, a die having a variable orifice, means for moving the draw-head relatively to the die to draw the tube through the die, a cam, means controlled by the cam for repeatedly decreasing and increasing the size of the orifice as the tube is being drawn through the die and means for supporting the inside of the tube.

3. Apparatus for varying the diameter of a tube, comprising, in combination, a drawhead adapted to grip the tube, a die having a variable orifice, a mandreladapted to provide interior support for the tube and having a tapered portion projecting through the orifice, means for moving the draw-head relatively to the die to draw the tube through the die, a cam, and means controlled by the cam for simultaneously varying'the orifice during movement of the draw-head and varying the position of the tapered portion of themandrel with respect to the die.

4. Apparatus for varying the diameter of a tube, comprising, in combination, a drawhead adapted to grip the tube, a die having an orifice through which the tube is drawn, a mandrel adapted to provide'interior support for the tube and having a tapered portion projecting into the die, the die having as its working members a plurality of balls arranged in an annular series and radially movable to vary the drawing orifice of the die, a cam, means operated by the cam for simultaneously varying said orifice and moving the mandrel with respect to the orifice, and means for moving the draw-head to draw the tube through the die in timed relation to the operation of the cam.

5. Apparatus for varyin the diameter of a tube, comprising, in com in-ation, a drawhead adapted to grip the tube, a die having a variable orifice, means for moving the drawhead relatively to the die to draw the tube through the die, a cam, means controlled by the cam for causing a cycle of variations in the orifice in timed relation to the movement of the draw-head, and means operable automatically for stopping movement of the draw-head and the cam on completion of said cycle of variations.

6. Apparatus for varying the diameter of a tube, comprising, in'combination, a drawhead adapted to grip the tube, a die having a variable orifice, means for moving the drawhead relatively to the die to draw the tube through the die, a rotary cam, means controlled by the cam for varying the orifice in timed relation to the movement of the drawhead, and means operable automatically for stopping movement of thedraw-head and the cam on completion of a cycle of movement of the cam.

7. Apparatus for varying the diameter of a tube, comprising, in combination, a rotatable hollow spindle, a hollow cage secured within the spindle, a mandrel cage and adapted to provide interior support for the tube, a plurality of balls retained by the cage and adapted to bear on the outside of the tube, an annular member surrounding the cage and having a tapered inner peripheral wall engaging the balls and serving to press them radially inward pon the tube, the mandrel having a tapere end portion paralleling said wall, and a cam operating to move said annular member and mandrel axially with respect to the cage to vary the radial position of said balls.

8. Apparatus for varyin the diameter of a tube, comprising, in com ination, a rotatable hollow spindle, a hollow cage secured within the spindle and free to rotate independently therein, a mandrel rojecting into the cage and adapted to provi e interior support for the tube, a pluralit of balls retained by the cage and adapted to ear upon the outside of the tube, an annular member surrounding the cage and having a tapered peripheral wall engaging the balls and serving.

to press them ra ially inward upon the tube, the mandrel havin a tapered end portion paralleling said wa l, and a cam operatin to move said annular member and mandre axially with respect to the cage to vary the radial position of said balls.

9. Apparatus for varyin the diameter of a tube, comprising, in com ination, a rotatable hollow spindle, a hollow cagesecured within the spindle, a mandrel (projecting into the cage and adapted to provi e interior support for the tube, aplurality of balls retained by the cage and'adapted to bear upon the'outslde of the tube, an annular member surrounding the cage and having a ta ered 1n-, ner peripheral wall engaging the alls and serving 'to press them radlally inward upon the tube, the mandrel having a tapered end portion paralleling said wall, a cam operating to cause variable axial'movement of said annular member and mandrel to vary the radial position of said balls, and means for drawing the tube through the cageat a-predetermined rate during the" operation of the cam.

h 10. Apparatus for varying the diameter of a tube, comprising,- in combination a rotatable'hollow spindle, a hollow cage secured within the spindle, a niandrel projecting support for the-tube, a plurality of balls retained by the cage and adapted to hear u on the outside of the tube, anannular mem er surrounding thecage and -having a tapered inner peripheral wall engaging the balls and serving to press them radially inward upon the tube, the mandrel having a tapered end portion paralleling said wall, a hollow shaft .connectedto the annular member and housing the mandrel, means for introducing oil into the hollow shaft to lubricate the balls,

projecting into the.

11. Apparatus for varying the diameter of a tube, comprising, in combination, a drawhead adapted to grip the tube, a die having a variable orifice, means for moving the draw-head relatively to. the die-to draw the 'tube through the die, and cam actuated means for repeatedly decreasing and increasing the size of the orifice as the tube is being drawn therethrou h.

12. Apparatus or varying the diameter of atube, comprising, incomb'ination, a drawhe'ad adapted to grip the tube, a die having a variable orifice, means for moving the drawhead relatively through the die, means for varying the orifice in timed relation to the draw-head, and automatically actuated means for stopping movement of the draw-head after the orifice has undergone a predetermined variation.

13. Apparatusfor varying the diameter of a tube, comprising in combination, a drawhead to grip the tube,"a die having a variable orifice, means for moving the draw-head to draw the tube through the die, die-controllingmeans for carrying the orifice in timed relation to the movement of the draw-head, and automatically .actuated means for stopping the movement of the draw-head and the operation of the die-controllin means after the orifice has undergone a pre etermined variation.

14:. Apparatus for varying the diameter of a tube comprising, in combination, a slidable mandrel adapted to provide interior support for the tube, an annular series of balls engaging the tube and mounted to revolve in a flxed plane about the'tube, a slidable and rotatable annular member serving to press the balls into engagement with the tube, said member having a tapered inner peripheral wall and said mandrel having a correspondingly tapered portion, means for simultaneously drawing the tube in one direction with respect to the balls and dralwin the mandrel and said member in the opposite direction to contract the orbit of the balls, and independent means for rotating said member. into the cage and adapted to provide interior tube, anannular member surrounding the cage and having a tapered inner peripheral wall engaging the balls and serving to press the balls inward upon the tube,;the mandrel having a tapered portion paralleling said to the die to draw thetubewall, and means for movingsaid annular member and said mandrel axially with respect to tghg cage to vary the radial position of said a ls.

16. Apparatus for varying the diameter of a tube, comprising, in combination, a tubular cage mounted to rotate in a relatively fixed plane, a mandrel projecting into the cage and adapted to provide interior support for the tube, a plurality of balls retained by the cage and adapted to bear upon the outside of the tube, an annular member surrounding the cage and having a tapered inner peripheral wall engaging the balls and serving to press the balls inward upon the tube, the mandrel having a tapered portion paralleling said wall, means for moving said annular member and said mandrel axially with respect to the cage to vary the radial position of said balls, and means forrotating said annular member.

17. Apparatus for varying the diameter of a tube, comprising, in combination, a tubular cage mounted to rotate in a relatively fixed plane, a mandrel projecting into the ca e and adapted to provide interior support or the tube, a plurality of balls retained by the cage and adapted to bearupon the outside of the tube, .an annular member surrounding the cage and having a tapered inner peripheral wall engaging the balls and serving to press the balls inward upon the tube, the mandrel having a tapered portion paralleling said wall, and means for simultaneously drawing the tube in one direction through the ca e and drawing the mandrel and annular mem er in the opposite direction to force the balls inward upon the tube.

18. Apparatus for varying the diameter of a tube, comprising, in combination, a tubular cage mounted to rotate in a relatively fixed plane, a mandrel projecting into the cage and adapted to provide interior support for the tube, a plurality of balls retained by the cage and adapted to bear upon the outside of the tube, an annular member surrounding the cage and having a tapered inner peripheral wall engaging the balls and serving to press the balls inward upon the tube, the mandrel having a tapered portion paralleling said wall, means for simultaneously drawing the tube in one direction through the cage and drawing the mandrel and the annular member in the opposite direction to force the balls inward upon the tube, and separate means for rotating said annular member.

19. Apparatus for varying the diameterof a tube, comprising, in combination, a rotatable hollow spindle, a tubular cage mounted within the spindle and independently rotatable therein in a fixed plane, a mandrel projecting into the cage and adapted to provide interior support for the tube, a plurality of balls retained by the cage and adapted to bear upon the outside of the tube, an annular member surrounding the cage and having splined connection with the spindle, said member having a tapered inner peripheral wall engaging the balls and serving to press the balls radially inward upon the tube, the mandrel'having a tapered portion paralleling said wall, and means for moving said annular member and saidmandrel axially with respect to the cage to vary the radial position of said balls.

20. Apparatus for varying the diameter of a tube, comprising, in combination, a die having a variable orifice, a cam for varying the orifice, a draw-head for drawing the tube through the orifice, a feed-screw for drawing the draw-head, a drive-shaft, a train of gears transmitting motion from the drive-shaft to the feed-screw, and a separate train of gears of relatively lower speed ratio for transmitting motion from the drive-shaft to the cam.

21. Apparatus for varying the diameter of a tube, comprising, in combination, a die havin a variable orifice, a cam for varying the orifice, a draw-head for drawing the tube through the orifice, a feed-screw for drawing the draw-head, a drive-shaft, a train of gears for transmitting action from the drive-shaft to the feed-screw, a separate train of gears of relatively lower speed ratio for transmitting motion from the drive-shaft to the cam, a driving pulley, a clutch for connectin the shaft to the pulley, and a trip operab e on completion of a single rotation of the cam to disconnect the clutch.

22. In combination a hollow spindle, a d1e carried thereb I and having rotatingbodies as working mem ers, means for drawing work through the die and means for introducing fluid into the spindle and thence 1nto said working members.

23. In combination a hollow spindle, a d1e carried thereby, a mandrel within the spindle and projecting through the die, means for drawing work from the mandrel through the die and means for introducing fluid under pressure into the spindle whereby the flllld will flow into the die and between the mandrel I and the work.

24. In combination a die having rotating bodies as working members; a mandrel cooperating with the die, means for drawing a tube between the mandrel and said die, and means for passing fluid under pressure between-the mandrel and said tube and through said working members.

25. Apparatus for varying the diameter of a tube, comprising in combination a drawhead adapted to grip the tube, a die having rolling members, a cage for said rolling members, connecting means for moving said cage and a cam for moving the connecting means.

26. Apparatus for varying the diameter of a tube,'comprising in combination a drawhead adapted to grip the tube, a die having rolling members, a cage for said rolling members, connecting means for moving said cage the connecting means,

and a cam for moving 7 to driving mechanism said cam being geare for said drawhead.

27. Apparatus for varying the diameter of a tube, comprising in combination a drawhead adapted to grip the tube, means for moving said drawhead longitudinally with respect to the tube, a die havingrolling members, a cage for said rolling members, connecting means for moving said cage and a cam for moving the connecting means, said cam being rotated by a common driving means for said cam and said drawhead.

In testimony whereof I have signed this specification this 1st day of November, 1926.

FRIEDERIOH Mt TLLER. 

